JP2012053954A - Manufacturing method of magnetic recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a magnetic recording medium with excellent patterns.SOLUTION: In a manufacturing method of a patterned medium which includes formation of a mask having rugged patterns on a magnetic recording layer and a deactivation of magnetic property in a region of the magnetic recording layer corresponding to the recess of the mask, the radiation of ion beam via an injection depth adjustment layer provided on the magnetic recording layer includes deactivation of magnetic property of the magnetic recording layer and the thickness of the injection depth adjustment layer is decreased as the deactivation of magnetic property takes place and the ion beam inversion depth becomes deeper.

Description

  Embodiments described herein relate generally to a method for manufacturing a magnetic recording medium such as a patterned medium.

  In recent years, a dramatic increase in storage capacity in a recording medium such as a hard disk has been desired. In order to meet the demand, development of a magnetic recording medium having a high storage capacity is underway.

  In a magnetic recording medium used for a current hard disk, a certain area of a thin film containing a polycrystalline body of magnetic fine particles is recorded as one bit. In order to increase the recording capacity of the recording medium, the recording density must be increased. That is, the recording mark size that can be used for recording per bit must be reduced. However, if the recording mark size is simply reduced, the influence of noise depending on the shape of the magnetic fine particles cannot be ignored. If the particle size of the magnetic fine particles is reduced in order to reduce noise, recording cannot be maintained at room temperature due to thermal fluctuation.

  In order to avoid these problems, a bit patterned medium (BPM) has been proposed in which a recording material is divided in advance by a non-recording material and recording / reproduction is performed using a single magnetic dot as a single recording cell.

  Further, in the magnetic recording medium incorporated in the HDD, a problem that the improvement of the track density is hindered due to the interference between adjacent tracks has become apparent. In particular, reduction of the fringe effect of the recording head magnetic field is an important technical issue. In order to solve this problem, a discrete track type patterned medium (DTR medium) that processes a magnetic recording layer to physically separate recording tracks has been proposed. With a DTR medium, it is possible to reduce a side erase phenomenon in which information on an adjacent track is erased during recording, a side read phenomenon in which information on an adjacent track is read out during reproduction, and the like. Therefore, the DTR medium is expected as a magnetic recording medium that can provide a high recording density. When a patterned medium is used in a broad sense, it includes a bit patterned medium and a DTR medium.

  As a method for manufacturing a patterned medium, there is a technique for forming a pattern of a magnetic region and a nonmagnetic region in a magnetic recording layer by deactivating the magnetism of the magnetic recording layer. In this technique, in order to obtain a magnetic recording medium having an excellent pattern, it is important to deactivate magnetism accurately and uniformly in a target region.

Japanese Patent Laid-Open No. 2008-077756

  An object of the present invention is to provide a method for manufacturing a magnetic recording medium having an excellent pattern.

  According to the embodiment, there is provided a method of manufacturing a patterned medium including forming a mask having a concavo-convex pattern on a magnetic recording layer and deactivating magnetism in a region of the magnetic recording layer corresponding to a concave portion of the mask. Including deactivating the magnetism of the magnetic recording layer by irradiation of an ion beam through an implantation depth adjusting layer provided on the magnetic recording layer, and the implantation proceeds as the deactivation of the magnetism progresses. Provided is a method of manufacturing a patterned medium in which the depth adjustment layer thickness is reduced and the ion beam penetration depth is increased.

FIG. 3 is a plan view along the circumferential direction of the discrete track medium (DTR medium) according to the embodiment. The top view which follows the circumferential direction of the bit patterned medium (BPM) which concerns on embodiment. Sectional drawing which shows the manufacturing method of the magnetic-recording medium based on 1st Embodiment. Sectional drawing which shows an example of the conventional manufacturing method. Sectional drawing which shows an example of the conventional manufacturing method. Sectional drawing which shows the manufacturing method which concerns on embodiment. Sectional drawing which shows the conventional ion implantation, and the figure which shows the breadth to the side. Sectional drawing which shows the ion implantation which concerns on embodiment, and the figure which shows the spreading to the side. The figure which shows distribution of the ion with respect to the depth direction in an ion beam. Sectional drawing which shows the manufacturing method of the magnetic-recording medium based on 2nd Embodiment. Sectional drawing which shows the manufacturing method of the magnetic-recording medium based on 3rd Embodiment. Sectional drawing which shows the manufacturing method of the magnetic-recording medium based on 4th Embodiment. 1 is a perspective view showing a magnetic recording apparatus equipped with a magnetic recording medium manufactured according to an embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[Magnetic recording medium]
FIG. 1 is a plan view along the circumferential direction of a discrete track medium (DTR medium) which is an example of a magnetic recording medium according to the embodiment. As shown in FIG. 1, servo areas 210 and data areas 220 are alternately formed along the circumferential direction of the magnetic recording medium 100. The servo area 210 includes a preamble part 211, an address part 212, and a burst part 213. The data area 220 includes a discrete track 221 in which adjacent tracks are separated from each other.

  FIG. 2 is a plan view along the circumferential direction of a bit patterned medium which is another example of the magnetic recording medium according to the embodiment. In the magnetic recording medium 100, magnetic dots 222 are formed in the data area 220.

[Production method]
(First embodiment)
A method for manufacturing a magnetic recording medium according to the first embodiment will be described with reference to FIGS.

As shown in FIG. 3A, a magnetic recording layer 2, a diamond-like carbon (DLC) layer 3, a first hard mask 4, a second hard mask 5, and a third hard mask 6 are formed on a glass substrate 1. Then, a resist 7 is laminated. For example, a 40 nm thick soft magnetic layer (CoZrNb) (not shown), a 20 nm thick orientation control underlayer (Ru) (not shown), and a 20 nm thick magnetic recording layer 2 are formed on a glass substrate 1. (CoCrPt—SiO ₂ ), a DLC layer 3 having a thickness of 2 nm, a first hard mask (Mo) 4 having a thickness of 30 nm, a second hard mask (C) 5 having a thickness of 30 nm, and a third having a thickness of 3 nm. A hard mask (Si) 6 is formed. A resist 7 is spin-coated on the third hard mask 6 so as to have a thickness of 80 nm. For example, a general photoresist is used as the resist. On the other hand, for example, a stamper on which a predetermined uneven pattern corresponding to the pattern shown in FIG. 1 or 2 is formed is prepared. The stamper is manufactured through EB drawing, Ni electroforming, and injection molding. The stamper is arranged so that the uneven surface thereof faces the resist 7.

  As shown in FIG. 3B, a stamper is imprinted on the resist 7, and the uneven pattern of the stamper is transferred to the resist 7. Then remove the stamper. FIG. 3B shows a state in which the stamper is removed after imprinting. Resist residue remains on the bottom of the concave portion of the concave-convex pattern transferred to the resist 7.

As shown in FIG. 3C, the resist residue in the recesses is removed by dry etching, and the surface of the third hard mask 6 is exposed. In this step, for example, CF ₄ is used as a process gas by an inductively coupled plasma (ICP) RIE apparatus, the chamber pressure is 0.1 Pa, the coil RF power and the platen RF power are 100 W and 50 W, respectively, and the etching time is 60 Done as seconds.

As shown in FIG. 3D, using the patterned resist 7 as a mask, the pattern is transferred to the third hard mask 6 using ion beam etching, and the second hard mask 5 is exposed in the recesses. In this step, CF ₄ is used as a process gas by an inductively coupled plasma (ICP) RIE apparatus, the chamber pressure is 0.1 Pa, the coil RF power and the platen RF power are 100 W and 50 W, respectively, and the etching time is 20 Done as seconds.

As shown in FIG. 3E, using the patterned third hard mask 6 as a mask, the second hard mask 5 made of C is etched to transfer the pattern, and the first hard mask 4 is formed in the recess. To expose the surface. For example, by using an inductively coupled plasma (ICP) RIE apparatus, O ₂ is used as the process gas, the chamber pressure is 0.1 Pa, the coil RF power and the platen RF power are 100 W and 50 W, respectively, and the etching time is 30 seconds. .

As shown in FIG. 3 (f), the magnetism of the region corresponding to the pattern concave portion of the magnetic recording layer 2 is deactivated through the first hard mask 4 made of Mo and the DLC layer 3. Thereby, a nonmagnetic region 8 is formed in the magnetic recording layer 2. The deactivation of magnetism uses, for example, a mixed gas of He and N ₂ having a partial pressure ratio of 1: 3 by an ECR (electron cyclotron resonance) ion gun, a gas pressure of 0.04 Pa, a microwave power of 1000 W, and a pressurization voltage of 5000 V. The processing time is 60 seconds.

  As shown in FIG. 3G, the remaining first hard mask (Mo) 4 is removed together with the upper layer. This step is performed, for example, by immersing the medium in aqueous hydrogen peroxide and holding it for 1 minute. As a result, the first hard mask 4 is peeled from the DLC layer 3.

  As shown in FIG. 3H, a patterned medium is obtained by forming the protective layer 11 by CVD (chemical vapor deposition) and applying a lubricant.

  In the manufacturing method according to the first embodiment, the first hard mask 4 functions as an implantation depth adjustment layer for adjusting the ion beam implantation depth. The first hard mask 4 as the implantation depth adjusting layer is formed at the stage of laminating the layers shown in FIG.

(Difference from conventional manufacturing method)
Differences between the manufacturing method according to the embodiment and the conventional manufacturing method will be described with reference to FIGS.

  4 and 5 show a conventional manufacturing method, and FIG. 6 shows a manufacturing method according to the embodiment. In the conventional manufacturing method, as shown in FIG. 4, the magnetic recording layer 2 is deactivated through the mask 10 by, for example, a plurality of ion beams (A to C) having different energies. In this method, the magnetic recording layer 2 is deactivated without causing etching of the mask 10 by irradiating an ion beam with relatively high energy. The nonmagnetic region 8 formed thereby spreads in the lateral direction and is deactivated due to the use of a plurality of ion beams. Alternatively, as shown in FIG. 5, the magnetic recording layer 2 is deactivated without a mask. In this case, an ion beam having a relatively low energy is used, and part of the magnetic recording layer 2 is removed as the deactivation progresses, resulting in the formation of a medium with irregularities on the surface.

  In the manufacturing method according to the embodiment, as shown in FIG. 6, the ion beam is irradiated onto the magnetic recording layer 2 through the implantation depth adjusting layer 9 (included in the mask 10 in the figure), and the mask 10 The magnetism is deactivated while reducing the film thickness of the film. This can prevent or minimize the spread of the nonmagnetic region 8 in the lateral direction and the occurrence of irregularities on the medium surface.

  This will be described in more detail with reference to FIGS. FIG. 7 is a cross-sectional view showing a conventional ion implantation and a diagram showing the spread to the side. FIG. 8 is a cross-sectional view illustrating ion implantation according to the embodiment and a diagram illustrating a spread to the side. FIG. 9 is a diagram showing ion distribution in the depth direction in the ion beam.

  In general, when ion beam irradiation is performed for deactivation of magnetism, a distribution of ions in the depth direction as shown in FIG. 9 occurs. In FIG. 9, the horizontal axis indicates the depth, and the vertical axis indicates the amount of ions at a specific depth. As shown in FIG. 9, the amount of ions to be implanted is not constant over the entire depth, but has a distribution in which the amount of ions has a peak at a certain depth. For this reason, when the magnetic recording layer is simply irradiated with a single ion beam, a portion where the deactivation is sufficient and a portion where the deactivation is insufficient are generated according to the ion distribution in the depth direction.

  In the conventional manufacturing method, in order to avoid such inhomogeneous deactivation, as shown in FIG. 7A, a plurality of types of ion beams having different valences or a plurality of ion beams having different energies are used. . That is, a plurality of ion beams whose peaks are shifted from each other are used to supplement the amount of ions to uniformly deactivate magnetism. However, as shown in FIG. 7B, the plurality of ion beams have different lateral spreads, and as a result, the nonmagnetic region 8 is formed wider than the shape of the recess in the mask 10. , Fringe characteristics deteriorate.

  On the other hand, in the manufacturing method according to the embodiment, the magnetic recording layer 2 is deactivated via the implantation depth adjusting layer 9 that decreases with deactivation. With such a configuration, the formation of irregularities on the surface of the magnetic recording layer 2 can be prevented. Furthermore, even when a single ion beam is used, it becomes possible to deactivate the magnetism uniformly in the depth direction. This is because the ion distribution due to the ion beam slides downward as the film thickness of the implantation depth adjusting layer 9 decreases, and the peak of the ion beam passes through all parts in the depth direction of the magnetic recording layer 2. Also, since a single ion beam is used, the implantation energy can be kept low, and the magnetism can be deactivated by suppressing the spread in the lateral direction (FIG. 8a).

(Ion beam penetration depth)
In the embodiment, the “ion beam penetration depth” is defined as follows using FIG. 9. That is, the “ion beam penetration depth” is the distance (C) from the surface (A) of the implantation depth adjusting layer 9 at the start of deactivation to the tip of the ion distribution at a certain time. Further, the distance (B) from the surface (A) of the implantation depth adjusting layer 9 at the start of deactivation to the peak of the ion amount at a certain time point is defined as “ion penetration peak”. These can be obtained by simulation such as TRIM. Further, how much ions actually penetrate can be measured by a technique such as cross-sectional TEM-EELS or TEM-EDX mapping. The ion beam basically attenuates when passing through a heavy element or high-density film, and changes little when passing through a light element or low-density film. Therefore, in deactivation of the magnetic recording layer 9, it is important to examine “ion beam penetration depth” or “ion penetration peak”.

  In the embodiment, preferably, the ion beam penetration depth when deactivation is completed is positioned below the magnetic recording layer 2. When the deactivation is completed, the ion beam reaches the entire magnetic recording layer 2 so that the magnetic recording layer 2 is deactivated without shortage. Preferably, the ion beam penetration depth at the start of deactivation is located in the magnetic recording layer 2. If the peak of the ion beam is below the magnetic recording layer 2 at the start of irradiation, sufficient deactivation may not be expected on the surface side of the magnetic recording layer 2, but the ion beam penetration depth at the start of deactivation may not be expected. Is located in the magnetic recording layer 2, sufficient deactivation of the magnetism can be performed. More preferably, the ion beam penetration depth at the start of deactivation is located above the magnetic recording layer 2. Thereby, it is ensured that the peak of the ion beam passes through a shallow region of the magnetic recording layer 2, and sufficient deactivation can be performed.

(Second Embodiment)
A method of manufacturing a magnetic recording medium according to the second embodiment will be described with reference to FIGS.

As shown in FIG. 10A, on a glass substrate 1, a 40 nm thick soft magnetic layer (CoZrNb) (not shown), a 20 nm thick orientation control underlayer (Ru) (not shown), and 20 nm thick magnetic recording layer 2 (CoCrPt—SiO ₂ ), 2 nm thick DLC layer 3, 3 nm thick first hard mask (Mo) 4, 20 nm thick second hard mask (C) 5 Then, a third hard mask (Si) 6 having a thickness of 3 nm is formed. A resist 7 is spin-coated on the third hard mask 6 so as to have a thickness of 80 nm. For the resist 7, for example, a general photoresist is used. On the other hand, for example, a stamper on which a predetermined uneven pattern corresponding to the pattern shown in FIG. 1 or 2 is formed is prepared. The stamper is manufactured through EB drawing, Ni electroforming, and injection molding. The stamper is arranged so that the uneven surface thereof faces the resist 7.

  As shown in FIG. 10B, a stamper is imprinted on the resist 7, and the uneven pattern of the stamper is transferred to the resist 7. Then remove the stamper. FIG. 10B shows a state in which the stamper is removed after imprinting. Resist residue remains on the bottom of the concave portion of the concave-convex pattern transferred to the resist 7.

As shown in FIG. 10C, the resist residue in the recesses is removed by dry etching, and the surface of the third hard mask 6 is exposed. In this step, for example, CF ₄ is used as a process gas by an inductively coupled plasma (ICP) RIE apparatus, the chamber pressure is 0.1 Pa, the coil RF power and the platen RF power are 100 W and 50 W, respectively, and the etching time is 60 Done as seconds.

As shown in FIG. 10D, the patterned resist 7 is used as a mask, the pattern is transferred to the third hard mask 6 using ion beam etching, and the second hard mask 5 is exposed in the recesses. In this step, CF ₄ is used as a process gas by an inductively coupled plasma (ICP) RIE apparatus, the chamber pressure is 0.1 Pa, the coil RF power and the platen RF power are 100 W and 50 W, respectively, and the etching time is 20 Done as seconds.

As shown in FIG. 10E, using the patterned third hard mask 6 as a mask, the second hard mask 5 made of C is etched to transfer the pattern, and the first hard mask 4 is formed in the recess. To expose the surface. For example, by using an inductively coupled plasma (ICP) RIE apparatus, O ₂ is used as the process gas, the chamber pressure is 0.1 Pa, the coil RF power and the platen RF power are 100 W and 50 W, respectively, and the etching time is 20 seconds. .

  As shown in FIG. 10F, the implantation depth adjusting layer 9 is formed on the medium on which the concave / convex pattern is formed up to the second hard mask 5. For example, a 30 nm thick Cr film is formed.

As shown in FIG. 10G, the magnetism of the region corresponding to the pattern concave portion of the magnetic recording layer 2 is changed through the implantation depth adjusting layer 9 made of Cr, the first hard mask 4 made of Mo, and the DLC layer 3. Deactivate. Thereby, a nonmagnetic region 8 is formed in the magnetic recording layer 2. This deactivation of the magnetism is, for example, using an ECR (electron cyclotron resonance) ion gun using a mixed gas of He and N ₂ with a partial pressure ratio of 1: 1, a gas pressure of 0.04 Pa, a microwave power of 1000 W, and a pressurizing voltage. It is performed at 5000 V and a processing time of 100 seconds.

As shown in FIG. 10 (h), the remaining implantation depth adjusting layer 9 is removed. This step is performed by, for example, an RIE apparatus using Cl ₂ as a process gas, a chamber pressure of 1 Pa, a power of 400 W, and an etching time of 20 seconds.

As shown in FIG. 10I, the remaining first hard mask (Mo) 4 is removed together with the upper layer. This step is performed, for example, by immersing the medium in hydrogen peroxide solution and holding it for 1 minute. As a result, the first hard mask 4 is peeled from the DLC layer 3. Further, the surface is cleaned with H ₂ plasma.

  As shown in FIG. 10 (j), a patterned medium is obtained by forming the protective layer 11 by CVD (chemical vapor deposition) and applying a lubricant.

  In the manufacturing method according to the second embodiment, the implantation depth adjustment layer 9 is provided independently of the first hard mask 4. Therefore, the first hard mask 4 can be thinly formed. As shown in FIG. 10F, the implantation depth adjusting layer 9 is formed after forming an uneven pattern on the mask.

(Third embodiment)
A method for manufacturing a magnetic recording medium according to the third embodiment will be described with reference to FIGS. However, since the steps of FIGS. 11A to 11E can be performed in the same manner as the steps of FIGS. 10A to 10E of the second embodiment, description thereof will be omitted.

  As shown in FIG. 11F, using the patterned second hard mask 5 as a mask, the first hard mask 4 made of Mo is etched to transfer the pattern, and the surface of the DLC layer 3 is formed by the recess. Expose. This process is performed by, for example, an ion milling apparatus using Ar as a process gas, a chamber pressure of 0.05 Pa, an acceleration voltage of 400 V, and a processing time of 10 seconds.

As shown in FIG. 11G, using the patterned first hard mask 4 as a mask, the DLC layer 3 is etched to transfer the pattern, and the surface of the magnetic recording layer 2 is exposed at the recesses. This process is performed using, for example, an inductively coupled plasma (ICP) RIE apparatus using O ₂ as a process gas, a chamber pressure of 0.1 Pa, a coil RF power and a platen RF power of 100 W and 50 W, respectively, and an etching time. It is performed as 20 seconds.

  As shown in FIG. 11 (h), the implantation depth adjusting layer 9 is formed on the medium on which the concave / convex pattern is formed up to the DLC layer 3. For example, a 30 nm-thick W film is formed.

As shown in FIG. 11 (i), the magnetism of the region corresponding to the pattern concave portion of the magnetic recording layer 2 is deactivated through the implantation depth adjusting layer 9 made of W. This step is performed, for example, with an ECR (electron cyclotron resonance) ion gun using N ₂ gas at a gas pressure of 0.04 Pa, a microwave power of 1000 W, a pressurization voltage of 5000 V, and a processing time of 50 seconds. By this process, the film thickness of the implantation depth adjusting layer 9 is reduced from 30 nm to 2 nm, for example.

  As shown in FIG. 11J, the remaining first hard mask (Mo) 4 is removed together with the upper layer. This step is performed, for example, by immersing the medium in hydrogen peroxide solution and holding it for 1 minute. As a result, the first hard mask 4 is peeled off from the DLC layer 3, the implantation depth adjusting layer 9 is formed on the nonmagnetic region 8 of the magnetic recording layer 2, and the DLC layer 3 is formed on the region where the magnetism is maintained. Remain. The film thickness of the remaining DLC layer 3 is, for example, 3 nm, the film thickness of the implantation depth adjusting layer 9 is, for example, 2 nm, and the resulting unevenness difference is 1 nm.

  As shown in FIG. 11 (k), a patterned medium is obtained by forming a protective layer 11 by CVD (chemical vapor deposition) and applying a lubricant.

  In the manufacturing method according to the third embodiment, the implantation depth adjustment layer 9 is provided independently of the first hard mask 4. Therefore, the first hard mask 4 can be thinly formed. As shown in FIG. 11 (h), the implantation depth adjusting layer 9 is formed after forming an uneven pattern on the mask.

(Fourth embodiment)
A method for manufacturing a magnetic recording medium according to the fourth embodiment will be described with reference to FIGS. However, since the steps of FIGS. 12A to 12E can be performed in the same manner as the steps of FIGS. 10A to 10E of the second embodiment, description thereof will be omitted.

  As shown in FIG. 12 (f), using the patterned second hard mask 5 as a mask, the first hard mask 4 made of Mo is etched to transfer the pattern, and the surface of the DLC layer 3 is formed by the recess. Expose. This step is performed by, for example, an ion milling apparatus using Ar as a process gas, a chamber pressure of 0.05 Pa, an acceleration voltage of 400 V, and a processing time of 10 seconds.

As shown in FIG. 12G, using the patterned first hard mask 4 as a mask, the DLC layer 3 is etched to transfer the pattern, and the surface of the magnetic recording layer 2 is exposed at the recesses. This process is performed using, for example, an inductively coupled plasma (ICP) RIE apparatus using O ₂ as a process gas, a chamber pressure of 0.1 Pa, a coil RF power and a platen RF power of 100 W and 50 W, respectively, and an etching time. It is performed as 20 seconds.

  As shown in FIG. 12 (h), the implantation depth adjusting layer 9 is formed on the medium on which the concavo-convex pattern is formed up to the DLC layer 3. For example, W having a thickness of 25 nm is formed.

As shown in FIG. 12 (i), the magnetism of the region corresponding to the pattern concave portion of the magnetic recording layer 2 is deactivated through the implantation depth adjusting layer 9 made of W. This step is performed, for example, with an ECR (electron cyclotron resonance) ion gun using N ₂ gas at a gas pressure of 0.04 Pa, a microwave power of 1000 W, a pressurization voltage of 5000 V, and a processing time of 50 seconds. By this treatment, all of the implantation depth adjusting layer 9 is etched, and the concave surface of the magnetic recording layer 2 is also etched by 3 nm, for example.

  As shown in FIG. 12J, the remaining first hard mask (Mo) 4 is removed together with the upper layer. This step is performed, for example, by immersing the medium in hydrogen peroxide solution and holding it for 1 minute. As a result, the first hard mask 4 is peeled off from the DLC layer 3, and the DLC layer 3 remains on the magnetic recording layer 2 where the magnetism is maintained. The film thickness of the remaining DLC layer 3 is, for example, 3 nm. On the other hand, the surface of the nonmagnetic region 8 is etched by 3 nm, so that the resulting unevenness difference is 6 nm.

  As shown in FIG. 12 (k), a patterned medium is obtained by forming a protective layer 11 by CVD (chemical vapor deposition) and applying a lubricant.

  In the manufacturing method according to the fourth embodiment, the implantation depth adjusting layer 9 is provided independently of the first hard mask 4. Therefore, the first hard mask 4 can be thinly formed. As shown in FIG. 12H, the implantation depth adjusting layer 9 is formed after forming an uneven pattern on the mask. In addition, as compared with the third embodiment, by forming the implantation depth adjusting layer 9 thinly, as shown in FIG. 12 (i), all of the implantation depth adjusting layer 9 disappears upon deactivation.

  In the manufactured magnetic recording medium, the thickness of various films and the depth of the unevenness can be easily measured using, for example, AFM (atomic force microscope), cross-sectional TEM (transmission electron microscopy), or the like. Further, the metal mask type and the composition ratio thereof can be easily measured by performing EDX (energy dispersive X-ray spectroscopy) analysis. By analyzing the medium after completion of processing by XPS (X-ray photoelectron spectroscopy) and analyzing the residual gas in the medium, it is possible to investigate the type of etching gas used in ion beam etching and its effect. The edge roughness can be measured by image analysis using AFM or planar SEM (scanning electron microscopy).

[Details of materials]
Below, the material which can be used with the manufacturing method of the patterned medium which concerns on embodiment is demonstrated.

(Injection depth adjustment layer)
The implantation depth adjusting layer 9 is provided for adjusting the penetration depth of ions by ion beam irradiation. As the deactivation proceeds, the thickness of the implantation depth adjusting layer 9 decreases, so that the ion beam penetration depth increases.

As the implantation depth adjusting layer 9, a resist material, various inorganic substances and metals, and compounds thereof can be used. When a resist material is used, a general photo-curing resist, thermosetting resist, SOG (Spin-On-Glass), or the like can be used. An imprint residue formed by imprinting a stamper after forming a resist material can be used as it is as an implantation depth adjusting layer. On the other hand, after forming the pattern of each mask, a resist material can be formed by vapor deposition or the like. When using an inorganic _{non-metallic, C, C x N y (} y ≦ x), Si, SiO 2, Si x N y (y ≦ 4x / 3), Si x C y (y ≦ 25x) be used as the Can do. When using metals, use precious metals such as Ag, Au, Cu, Pd, Pt, and Ru, and metals that can easily form compounds such as Al, Cr, Hf, Mo, Nb, Ta, Ti, V, W, and Zr. be able to. Materials that tend to make compounds during the process generally have a slow etch rate. The implantation depth adjusting layer 9 having a low etching rate is suitable because it can implant a sufficient amount of ions. In addition, since noble metals are difficult to produce implanted ion species and reaction products, there is an advantage that ions are not trapped in the implantation depth adjusting layer 9 and are easily implanted.

  The first hard mask 4 can also be used as the implantation depth adjustment layer 9. In this case, the implantation depth adjusting layer 9 is formed as the first hard mask 4 when each layer is formed (for example, the process of FIG. 3A).

  The injection depth adjusting layer 9 can also be used as a release layer. For example, a metal that is easily dissolved by an acid such as Mo or Cr can be used for peeling as it is after being used for adjusting the injection depth in the deactivation step. Ti and Ta can be removed with hydrofluoric acid. When a resist material is used as the implantation depth adjusting layer 9, it can be removed with a resist stripping solution. Further, a plurality of types of implantation depth adjustment layers 9 may be stacked to form a film. For example, by providing the implantation depth adjusting layer such as Ta having a low etching rate on the medium surface side and the implantation depth adjusting layer such as Mo on the substrate side as described above, sufficient ion implantation and peeling by weak acid can be performed. Can be realized.

  The initial film thickness of the implantation depth adjusting layer 9 can be determined according to the ion shielding property of the layer. For example, in the case of using a material having a high ion shielding property, the ion penetration depth becomes deeper as the implantation depth adjustment layer 9 becomes thinner. Therefore, the implantation depth adjustment layer 9 may be thin. On the other hand, when a material having low ion shielding properties is used, the ion penetration depth from the surface of the implantation depth adjustment layer 9 may become shallower as the implantation depth adjustment layer 9 is etched. In that case, the implantation depth adjusting layer 9 needs to be formed thicker. Whatever the ion shielding property, if the initial film thickness of the implantation depth adjusting layer 9 and the film thickness to be etched of the implantation depth adjusting layer 9 are too thin, the magnetic recording layer 2 is deactivated in the depth direction. There is a risk of shortage. Therefore, the initial film thickness of the implantation depth adjusting layer 9 and the film thickness to be etched must be appropriately selected according to the ion penetration depth. From the viewpoint of maintaining the robustness of the process, the thickness of the implantation depth adjusting layer 9 may be thicker than actually required. In the case where a layer serving as the first hard mask 4 and the implantation depth adjusting layer 9 is formed, the film thickness is preferably, for example, 10 to 40 nm, and particularly preferably 15 to 30 nm. On the other hand, the same applies to the case where the implantation depth adjusting layer 9 is formed after the concave / convex pattern of the mask is formed. By adjusting the thickness to form a film, it is possible to adjust whether the implantation depth adjusting layer 9 is completely lost or partially left by the magnetic deactivation.

(Resist)
As the resist 7, a UV curable resin, a general resist 7 mainly composed of novolak, or the like can be used. When a UV curable resin is used, the stamper material is preferably a material that transmits light such as quartz or resin. It can be cured by irradiating UV curable resin with ultraviolet rays. For example, a high-pressure mercury lamp may be used as the ultraviolet light source. When a general resist 7 mainly composed of novolak is used, a material such as Ni, quartz, Si, or SiC can be used for the stamper. The resist 7 can be cured by applying heat or pressure.

(Hard mask)
As the first to third hard masks, those having a composition different from that of the implantation depth adjusting layer 9 are preferably used. The difference in composition causes a difference in the etching rate and shielding property of these layers, and the spread of implanted ions from the film thickness direction and the film inner direction is prevented. When a metal such as Cr or Mo is used as the implantation depth adjusting layer 9, for example, a resist or a material mainly containing C is preferable because the selection ratio can be increased. Conversely, when C is used as the implantation depth adjusting layer 9, Si, Ta, Ti, or the like can be used as each hard mask. However, the first hard mask 4 can also be provided as the implantation depth adjusting layer 9.

  The first hard mask 4 can be made of a material that can be easily thinned. For example, a material having a higher reactivity with the stripping solution than the main component of the magnetic recording layer can be used. Specifically, Mo, Cr, Ta, V, Nb, Ta, Zr, Al, or the like can be used. When the thickness of the first hard mask 4 is provided as the implantation depth adjusting layer 9, it is preferably 10 to 40 nm, particularly preferably 20 to 30 nm. Moreover, when providing as a peeling layer, it is preferable that the film thickness of the 1st hard mask 4 shall be 1-5 nm, and it is preferable to set it as 3 nm especially.

  As the second hard mask 5, for example, a material mainly composed of carbon, CN, BC, or the like can be used. In particular, it is preferable to contain 70% or more of carbon. The thickness of the second hard mask 5 is preferably 15 to 100 nm, and more preferably 20 to 50 nm.

  As the third hard mask 5, Si, Ti, Ta, W, or the like can be used. In particular, it is preferable to use Si. The film thickness of the third hard mask 6 is preferably 2 to 5 nm, and particularly preferably 3 nm.

(Diamond-like carbon layer)
As a layer for preventing oxidation of the magnetic recording layer 2, a diamond-like carbon (DLC) layer 3 can be provided between the first hard mask 4 and the magnetic recording layer 2. The DLC layer 3 is mainly composed of carbon. The thickness of the DLC layer 3 can be 1 to 20 nm.

(substrate)
As the substrate 1, for example, a glass substrate, an Al-based alloy substrate, a ceramic substrate, a carbon substrate, a Si single crystal substrate having an oxidized surface, or the like can be used. As the glass substrate, amorphous glass or crystallized glass is used. Examples of the amorphous glass include general-purpose soda lime glass and aluminosilicate glass. Examples of crystallized glass include lithium-based crystallized glass. Examples of the ceramic substrate include sintered bodies mainly composed of general-purpose aluminum oxide, aluminum nitride, silicon nitride, etc., and fiber reinforced products thereof. As the substrate 1, it is also possible to use a substrate in which a NiP layer is formed on the surface of the above-described metal substrate or non-metal substrate using a plating method or a sputtering method. Further, as a method for forming a thin film on a substrate, the same effect can be obtained by using not only a sputtering method but also a vacuum deposition method or an electrolytic plating method.

(Soft magnetic backing layer)
The soft magnetic underlayer (SUL) has a part of the function of the magnetic head for passing a recording magnetic field from a single pole head for magnetizing the perpendicular magnetic recording layer in the horizontal direction and returning it to the magnetic head side. The recording layer has a function of applying a steep and sufficient vertical magnetic field to improve the recording / reproducing efficiency. For the soft magnetic underlayer, a material containing Fe, Ni, or Co can be used. Examples of such materials include FeCo alloys such as FeCo and FeCoV, FeNi alloys such as FeNi, FeNiMo, FeNiCr, and FeNiSi, FeAl alloys, FeSi alloys such as FeAl, FeAlSi, FeAlSiCr, FeAlSiTiRu, and FeAlO. Examples thereof include FeTa, FeTaC, and FeTaN, and FeZr alloys such as FeZrN. It is also possible to use a material having a fine structure such as FeAlO, FeMgO, FeTaN, FeZrN or the like having a granular structure in which fine crystal particles are dispersed in a matrix containing Fe of 60 at% or more. As another material of the soft magnetic backing layer, a Co alloy containing Co and at least one of Zr, Hf, Nb, Ta, Ti, and Y can also be used. The Co alloy preferably contains 80 at% or more of Co. In such a Co alloy, an amorphous layer is easily formed when the film is formed by sputtering. Since the amorphous soft magnetic material does not have magnetocrystalline anisotropy, crystal defects, and grain boundaries, it exhibits very excellent soft magnetism and can reduce the noise of the medium. Examples of suitable amorphous soft magnetic materials include CoZr, CoZrNb, and CoZrTa-based alloys.

  An underlayer may be further provided under the soft magnetic backing layer in order to improve the crystallinity of the soft magnetic backing layer or the adhesion to the substrate. As a material for such an underlayer, Ti, Ta, W, Cr, Pt, alloys containing these, or oxides or nitrides thereof can be used. An intermediate layer made of a nonmagnetic material may be provided between the soft magnetic backing layer and the recording layer. The intermediate layer has two functions of blocking the exchange coupling interaction between the soft magnetic backing layer and the recording layer and controlling the crystallinity of the recording layer. As the material for the intermediate layer, Ru, Pt, Pd, W, Ti, Ta, Cr, Si, alloys containing these, or oxides or nitrides thereof can be used.

  In order to prevent spike noise, the soft magnetic backing layer may be divided into a plurality of layers and antiferromagnetically coupled by inserting Ru of 0.5 to 1.5 nm. Further, a hard magnetic film having in-plane anisotropy such as CoCrPt, SmCo, or FePt, or a pinned layer made of an antiferromagnetic material such as IrMn or PtMn may be exchange-coupled with the soft magnetic layer. In order to control the exchange coupling force, a magnetic film (for example, Co) or a nonmagnetic film (for example, Pt) may be stacked on and under the Ru layer.

(Magnetic recording layer)
As the perpendicular magnetic recording layer, it is preferable to use a material mainly containing Co, containing at least Pt, and further containing an oxide. The perpendicular magnetic recording layer may contain Cr as necessary. As the oxide, silicon oxide and titanium oxide are particularly preferable. In the perpendicular magnetic recording layer, magnetic particles (crystal grains having magnetism) are preferably dispersed in the layer. The magnetic particles preferably have a columnar structure penetrating the perpendicular magnetic recording layer vertically. By forming such a structure, the orientation and crystallinity of the magnetic particles in the perpendicular magnetic recording layer are improved, and as a result, a signal noise ratio (SN ratio) suitable for high density recording can be obtained. In order to obtain such a structure, the amount of oxide to be contained is important.

  The oxide content of the perpendicular magnetic recording layer is preferably 3 mol% or more and 12 mol% or less, and more preferably 5 mol% or more and 10 mol% or less with respect to the total amount of Co, Cr, and Pt. The above range is preferable as the oxide content of the perpendicular magnetic recording layer because, when the perpendicular magnetic recording layer is formed, oxide is deposited around the magnetic particles, and the magnetic particles can be separated and refined. It is. When the oxide content exceeds the above range, the oxide remains in the magnetic particles, and the orientation and crystallinity of the magnetic particles are impaired. This is not preferable because a columnar structure in which magnetic particles penetrate vertically through the perpendicular magnetic recording layer is not formed. When the oxide content is less than the above range, separation and refinement of magnetic particles are insufficient, resulting in increased noise during recording and reproduction, and a signal-to-noise ratio (SN ratio) suitable for high-density recording. Since it cannot be obtained, it is not preferable.

  The Cr content of the perpendicular magnetic recording layer is preferably 0 at% or more and 16 at% or less, and more preferably 10 at% or more and 14 at% or less. The above range is preferable as the Cr content because the uniaxial crystal magnetic anisotropy constant Ku of the magnetic particles is not lowered too much, and high magnetization is maintained, resulting in recording / reproduction characteristics suitable for high-density recording and sufficient heat. This is because fluctuation characteristics can be obtained. When the Cr content exceeds the above range, Ku of the magnetic particles becomes small, so the thermal fluctuation characteristics deteriorate, and the crystallinity and orientation of the magnetic particles deteriorate, resulting in poor recording / reproducing characteristics. Therefore, it is not preferable.

  The Pt content in the perpendicular magnetic recording layer is preferably 10 at% or more and 25 at% or less. The above range for the Pt content is preferable because Ku required for the perpendicular magnetic layer is obtained, and the crystallinity and orientation of the magnetic particles are good. As a result, thermal fluctuation characteristics suitable for high-density recording, recording / reproduction This is because characteristics can be obtained. When the Pt content exceeds the above range, a layer having an fcc structure is formed in the magnetic particles, and crystallinity and orientation may be impaired. When the Pt content is less than the above range, it is not preferable because sufficient Ku for thermal fluctuation characteristics suitable for high-density recording cannot be obtained.

  The perpendicular magnetic recording layer contains at least one element selected from B, Ta, Mo, Cu, Nd, W, Nb, Sm, Tb, Ru, and Re in addition to Co, Cr, Pt, and oxide. Can do. By including the above elements, it is possible to promote miniaturization of magnetic particles or improve crystallinity and orientation, and to obtain recording / reproducing characteristics and thermal fluctuation characteristics suitable for higher density recording. The total content of the above elements is preferably 8 at% or less. If it exceeds 8 at%, phases other than the hcp phase are formed in the magnetic particles, so that the crystallinity and orientation of the magnetic particles are disturbed, resulting in recording / reproduction characteristics and thermal fluctuation characteristics suitable for high-density recording. Since it is not possible, it is not preferable.

  The perpendicular magnetic recording layer is composed mainly of at least one selected from the group consisting of CoPt alloys, CoCr alloys, CoPtCr alloys, CoPtO, CoPtCrO, CoPtSi, CoPtCrSi, and Pt, Pd, Rh, and Ru. A multilayer structure of an alloy and Co, and CoCr / PtCr, CoB / PdB, CoO / RhO, etc., to which Cr, B, and O are added can also be used.

  The thickness of the perpendicular magnetic recording layer is preferably 5 to 60 nm, more preferably 10 to 40 nm. Within this range, a magnetic recording / reproducing apparatus suitable for a higher recording density can be produced. If the thickness of the perpendicular magnetic recording layer is less than 5 nm, the reproduction output tends to be too low and the noise component tends to be higher. If the thickness of the perpendicular magnetic recording layer exceeds 40 nm, the reproduction output tends to be too high and the waveform tends to be distorted. The coercive force of the perpendicular magnetic recording layer is preferably 237000 A / m (3000 Oe) or more. When the coercive force is less than 237000 A / m (3000 Oe), the thermal fluctuation resistance tends to be inferior. The perpendicular squareness ratio of the perpendicular magnetic recording layer is preferably 0.8 or more. When the vertical squareness ratio is less than 0.8, the thermal fluctuation resistance tends to be inferior.

(Protective layer)
The protective layer 11 is provided for the purpose of preventing corrosion of the perpendicular magnetic recording layer and preventing damage to the medium surface when the magnetic head contacts the medium. Examples of the material of the protective layer 11 include those containing C, SiO ₂ , and ZrO ₂ . The thickness of the protective layer 11 is preferably 1 to 10 nm. Thereby, the distance between the head and the medium can be reduced, which is suitable for high-density recording. Carbon can be classified into sp ² bonded carbon (graphite) and sp ³ bonded carbon (diamond). Durability and corrosion resistance are superior to sp ³ -bonded carbon, but since it is crystalline, surface smoothness is inferior to graphite. Usually, the carbon film is formed by sputtering using a graphite target. In this method, amorphous carbon in which sp ² bonded carbon and sp ³ bonded carbon are mixed is formed. The one with a large proportion of sp ³ bonded carbon is called diamond-like carbon (DLC), which has excellent durability and corrosion resistance, and is amorphous, and thus has excellent surface smoothness. Therefore, it is used as a surface protective layer for magnetic recording media. ing. In DLC film formation by CVD (chemical vapor deposition), the source gas is excited and decomposed in plasma to generate DLC by chemical reaction. Therefore, by combining the conditions, DLC richer in sp ³ bond carbon can be obtained. Can be formed.

[Details of process]
Below, the process included in the manufacturing method of the patterned medium which concerns on embodiment is demonstrated.

(Mask deposition)
A first hard mask 4, a second hard mask 5, and a third hard mask 6 are formed in this order on the surface layer of a magnetic recording layer of a general magnetic recording medium. These can be formed by sputtering or CVD.

  Thereafter, a resist 7 is further formed thereon. A resist is uniformly applied to the surface of the medium by a spin coat method, a dip method, an ink jet method or the like. As the resist, a general photosensitive resin, thermoplastic resin, or thermosetting resin can be used. The resin is preferably etched by RIE using a gas containing oxygen or fluorine.

(imprint)
After forming the resist 7, a stamper is imprinted to transfer the uneven pattern to the resist 7. The imprint stamper is made of a material such as quartz, resin, Si, or Ni. When a stamper made of quartz or resin is used, a photosensitive resin (photoresist) that is cured by ultraviolet light is suitable. If the resist is a thermosetting or thermoplastic resin, the stamper is preferably Si or Ni because heat or pressure is applied during imprinting.

  For example, a resin stamper on which a recording track and servo information pattern is formed is pressed at 5 t for 60 seconds, and irradiated with ultraviolet light for 10 seconds, whereby the pattern is transferred to the resist. In the press, a stamper, a substrate, and a stamper are stacked on a lower plate of a die set and sandwiched between upper plates of the die set. A resist is applied to both sides of the substrate in advance. The stamper and the substrate face the uneven surface of the stamper and the resist film side of the substrate. Since the unevenness height of the pattern produced by imprinting is 30 to 50 nm, the residue is about 5 to 20 nm. If a fluorine-based release material is applied to the stamper, the stamper and the resist can be peeled off satisfactorily.

(Residue removal)
Resist residue removal after imprinting is performed by RIE (reactive ion etching). The plasma source is preferably ICP (Inductively Coupled Plasma) capable of generating high-density plasma at a low pressure, but ECR (Electron Cyclotron Resonance) plasma or a general parallel plate RIE apparatus may be used. When a photosensitive resin is used for the resist, O ₂ gas or CF ₄ gas, or a mixed gas of O ₂ and CF ₄ is used. When a Si-based material (for example, SOG (Spin-On-Glass)) is used for the resist 7, a fluorine gas RIE such as CF ₄ or SF ₆ is used. Residue removal ends when the third hard mask 6 under the resist is exposed.

(3rd hard mask patterning)
After imprinting and resist residue removal, the third hard mask 6 is patterned using the resist 7 on which the pattern is formed as a mask. For patterning the third hard mask 6, RIE may be used, or other ion beam etching apparatus may be used. The patterning of the third hard mask 6 is finished when the surface of the second hard mask 5 is exposed.

(Pattern of second hard mask)
After the patterning of the third hard mask 6, the second hard mask 5 is patterned. For patterning the second hard mask 5, RIE using a reactive gas may be used, or an ion beam etching method using a rare gas may be used. If etching with a reactive gas is performed, for example, SF ₆ , CF ₄ , Cl ₂ , HBr, or a gas obtained by adding a rare gas such as Ar to the gas as an assist is suitable. In the case of etching with a rare gas, a gas such as He, Ne, Ar, Xe, or Kr is suitable. Further, a reactive gas such as N ₂ or O ₂ can be mixed with a rare gas. The patterning of the second hard mask 5 is finished when the surface of the first hard mask 4 is exposed.

(Demagnetization of magnetic recording layer)
For patterning the magnetic recording layer 2, a magnetic deactivation method using ion beam irradiation is used. The fringe characteristic of the magnetic recording medium is improved by the deactivation of the magnetism. The magnetism deactivation refers to a process of weakening the magnetism of the region exposed from the mask of the magnetic recording layer 2 as compared with the magnetism of the region covered with the mask. Decreasing magnetism means softening, demagnetization or diamagnetization. Such a change in magnetism can be observed by measuring values such as Hn, Hs, and Hc with a VSM (sample vibration magnetometer) or a Kerr (magneto-optic Kerr effect) measuring device.

  The ion beam can be generated using a general ion implanter, an ECR ion shower device, a scanning focused ion beam device, a gas cluster ion beam device, or the like. With an ion implanter, ion beam irradiation can be performed on a large area with high throughput, and when an ECR ion source is used, the tact time per medium can be shortened with a high current density.

The ion species to be used is preferably a rare gas such as He, Ne, Ar, Kr, or Xe, a reactive gas such as N ₂ , O ₂ , or H ₂ , or a mixture thereof. If a rare gas is used, the magnetic recording layer can be made amorphous and the perpendicular orientation of magnetization can be weakened. If a reactive gas such as N ₂ , O ₂ , or H ₂ is used, it can react with the magnetic element of the recording layer or enter between the lattices, thereby reducing the magnetization. Further, if reactive gas and rare gas are mixed, higher reactivity can be obtained, and the deactivation tact time can be shortened.

  In ion beam irradiation, the amount of ions to be implanted follows a Gaussian distribution having a width that depends on the energy of the ions to be implanted and the material to be implanted. For implantation into a thin recording layer of about several tens of nanometers such as the patterned medium according to the embodiment, a relatively low energy ion beam is preferable. Preferably it is 100 keV or less, More preferably, it is 50 keV or less.

(Removal of the first hard mask)
After the patterning of the magnetic recording layer, the first hard mask 4 is peeled off. The second hard mask 5, the third hard mask 6, and the like remaining on the first hard mask 4 are peeled off together with the first hard mask 4. The peeling method can be appropriately selected according to the material used as the first hard mask 4. For example, a wet process, reactive ion etching, ion beam etching, or the like can be performed.

  In the case of a wet process, water, acid, alkali, or the like can be used as a stripping solution. By providing a protective layer made of DLC or the like between the first hard mask 4 as the peeling layer and the magnetic recording layer 2, the mask can be peeled without damaging the magnetic recording layer. The stripping solution is appropriately selected according to the material of the first hard mask 4. For example, high-temperature water, acidic aqueous solution, or alkaline aqueous solution can be used. Specifically, various acids and alkalis such as aqueous hydrogen peroxide, hydrochloric acid, nitric acid, hydrofluoric acid, sulfamic acid, aqueous ammonia, and aqueous sodium hydroxide can be used. After peeling, it is preferable to wash the magnetic recording medium with water or a solvent so that no peeling liquid remains.

(Protective layer formation and post-treatment)
The protective layer 11 made of carbon is preferably formed by a CVD method in order to improve the coverage to unevenness, but may be formed by a sputtering method or a vacuum evaporation method. According to the CVD method, a DLC film containing a large amount of sp ³ bonded carbon is formed. If the film thickness is 2 nm or less, the coverage is poor, and if it is 10 nm or more, the magnetic spacing between the recording / reproducing head and the medium increases and the SNR decreases, which is not preferable. A lubricant can be applied on the protective layer 11. As the lubricant, for example, perfluoropolyether, fluorinated alcohol, fluorinated carboxylic acid, or the like can be used.

(Formation of implantation depth control layer)
After the formation of the concavo-convex pattern of the mask, the implantation depth adjusting layer 9 can be formed. For example, in the manufacturing method according to the second embodiment, the implantation depth adjustment layer 9 is formed after the second hard mask 5 is patterned. In the manufacturing methods according to the third and fourth embodiments, the implantation depth adjusting layer 9 is formed after the DLC layer 3 is patterned. The film forming method can be appropriately selected depending on the material to be used. For example, it can be performed by sputtering, vapor deposition, or the like. After the formation of the implantation depth adjusting layer 9, the magnetic recording layer 2 is deactivated.

(Pattern of the first hard mask)
After the patterning of the second hard mask 5, the first hard mask 4 can be patterned. In particular, it is performed in the manufacturing method according to the third and fourth embodiments. For patterning the first hard mask 4, RIE using a reactive gas may be used, or an ion beam etching method using a rare gas may be used. The patterning of the first hard mask 4 is finished when the surface of the DLC layer 3 is exposed.

(Patterning of diamond-like carbon layer)
After the patterning of the first hard mask 4, the DLC layer 3 can be patterned. In particular, it is performed in the manufacturing method according to the third and fourth embodiments. For patterning the DLC layer 3, RIE using a reactive gas may be used, or an ion beam etching method using a rare gas may be used. The patterning of the DLC layer 3 is finished when the surface of the magnetic recording layer 2 is exposed.

[Magnetic recording device]
Next, a magnetic recording device (HDD) according to the embodiment will be described. FIG. 13 is a perspective view showing a magnetic recording apparatus on which the magnetic recording medium manufactured according to the embodiment is mounted.

  As shown in FIG. 13, the magnetic recording apparatus 150 according to the embodiment of the present invention is an apparatus using a rotary actuator. The patterned medium 100 is mounted on the spindle motor 140 and is rotated in the direction of arrow A by a motor (not shown) that responds to a control signal from a drive device control unit (not shown). The magnetic recording device 150 may include a plurality of patterned media 100.

  A head slider 130 for recording and reproducing information with respect to the patterned medium 100 is attached to the tip of a thin film suspension 154. A magnetic head is provided near the tip of the head slider 130. When the patterned medium 100 rotates, the pressing pressure by the suspension 154 balances with the pressure generated on the medium facing surface (ABS) of the head slider 130, and the medium facing surface of the head slider 130 is predetermined from the surface of the patterned medium 100. Holds with flying height.

  The suspension 154 is connected to one end of an actuator arm 160 having a bobbin portion for holding a drive coil (not shown). A voice coil motor 156 that is a kind of linear motor is provided at the other end of the actuator arm 160. The voice coil motor 156 can be composed of a drive coil (not shown) wound around the bobbin portion of the actuator arm 160, and a magnetic circuit composed of a permanent magnet and a counter yoke arranged to face each other so as to sandwich the coil. . The actuator arm 160 is held by ball bearings (not shown) provided at two positions above and below the pivot 157, and can be freely slid by a voice coil motor 156. As a result, the magnetic head can access any position on the patterned medium 100.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

[Example 1]
A magnetic recording medium was manufactured by the method shown in FIG. Furthermore, the performance was evaluated.

As shown in FIG. 3A, on a glass substrate 1, a 40 nm thick soft magnetic layer (CoZrNb) (not shown), a 20 nm thick orientation control underlayer (Ru) (not shown), and 20 nm thick magnetic recording layer 2 (CoCrPt—SiO ₂ ), 2 nm thick DLC protective film 3, 30 nm thick first hard mask (Mo) 4, 30 nm thick second hard mask (C) 5. A third hard mask (Si) 6 having a thickness of 3 nm was formed. A resist 7 was spin-coated on the third hard mask 6 so as to have a thickness of 80 nm. The stamper was arranged so that the uneven surface thereof faces the resist 7.

  As shown in FIG. 3B, a stamper was imprinted on the resist 7, and the uneven pattern of the stamper was transferred to the resist 7. Thereafter, the stamper was removed. Resist residue remained on the bottom of the concave portion of the concave-convex pattern transferred to the resist 7.

As shown in FIG. 3C, the resist residue in the recesses was removed by dry etching, and the surface of the third hard mask 6 was exposed. In this process, CF ₄ is used as a process gas by an inductively coupled plasma (ICP) RIE apparatus, the chamber pressure is 0.1 Pa, the coil RF power and the platen RF power are 100 W and 50 W, respectively, and the etching time is 60 seconds. Went as.

As shown in FIG. 3D, the patterned resist 7 is used as a mask, the pattern is transferred to the third hard mask 6 using ion beam etching, and the second hard mask 5 is exposed in the recesses. . In this process, CF ₄ is used as a process gas by an inductively coupled plasma (ICP) RIE apparatus, the chamber pressure is 0.1 Pa, the coil RF power and the platen RF power are 100 W and 50 W, respectively, and the etching time is 20 seconds. Went as.

As shown in FIG. 3E, using the patterned third hard mask 6 as a mask, the second hard mask 5 made of C is etched to transfer the pattern, and the first hard mask 4 is formed in the recess. The surface of was exposed. Using an inductively coupled plasma (ICP) RIE apparatus, O ₂ was used as a process gas, the chamber pressure was 0.1 Pa, the coil RF power and the platen RF power were 100 W and 50 W, respectively, and the etching time was 30 seconds.

As shown in FIG. 3 (f), the magnetism of the region corresponding to the pattern concave portion of the magnetic recording layer 2 was deactivated through the first hard mask 4 made of Mo and the DLC layer 3. As a result, a nonmagnetic region 8 was formed in the magnetic recording layer 2. For deactivation of magnetism, a gas mixture of He and N ₂ with a partial pressure ratio of 1: 3 is used with an ECR (electron cyclotron resonance) ion gun, gas pressure is 0.04 Pa, microwave power is 1000 W, pressurization voltage is 5000 V, treatment The time was 60 seconds.

  As shown in FIG. 3G, the remaining first hard mask (Mo) 4 was removed together with the upper layer. This step was performed by immersing the medium in aqueous hydrogen peroxide and holding it for 1 minute. As a result, the first hard mask 4 was peeled off from the DLC layer 3.

  As shown in FIG. 3H, a protective layer 11 was formed by CVD (chemical vapor deposition), and a lubricant was applied to obtain a patterned medium.

  The produced medium was mounted on a drive and a fringe test was performed. The magnetic Land width of the medium was 54 nm, the Groove width was 16 nm, the effective recording head width (MWW) was 80 nm, the effective reproducing head width (MRW) was 50 nm, and error rate measurement was performed after 1000 adjacent recordings. The error rate was 10 −5 or less, and it was confirmed that the DTR medium operated without any problem.

[Example 2]
A magnetic recording medium was manufactured by the method shown in FIG. Furthermore, the performance was evaluated.

As shown in FIG. 10A, on a glass substrate 1, a 40 nm thick soft magnetic layer (CoZrNb) (not shown), a 20 nm thick orientation control underlayer (Ru) (not shown), and 20 nm thick magnetic recording layer 2 (CoCrPt—SiO ₂ ), 2 nm thick DLC layer 3, 3 nm thick first hard mask (Mo) 4, 20 nm thick second hard mask (C) 5 Then, a third hard mask (Si) 6 having a thickness of 3 nm was formed. A resist 7 was spin-coated on the third hard mask 6 so as to have a thickness of 80 nm. The stamper was arranged so that the uneven surface thereof faces the resist 7.

  As shown in FIG. 10B, a stamper was imprinted on the resist 7, and the uneven pattern of the stamper was transferred to the resist 7. Thereafter, the stamper was removed. Resist residue remained on the bottom of the concave portion of the concave-convex pattern transferred to the resist 7.

As shown in FIG. 10C, the resist residue in the recesses was removed by dry etching, and the surface of the third hard mask 6 was exposed. In this process, CF ₄ is used as a process gas by an inductively coupled plasma (ICP) RIE apparatus, the chamber pressure is 0.1 Pa, the coil RF power and the platen RF power are 100 W and 50 W, respectively, and the etching time is 60 seconds. Went as.

As shown in FIG. 10D, the patterned resist 7 is used as a mask, the pattern is transferred to the third hard mask 6 using ion beam etching, and the second hard mask 5 is exposed in the recesses. . In this process, CF ₄ is used as a process gas by an inductively coupled plasma (ICP) RIE apparatus, the chamber pressure is 0.1 Pa, the coil RF power and the platen RF power are 100 W and 50 W, respectively, and the etching time is 20 seconds. Went as.

As shown in FIG. 10E, using the patterned third hard mask 6 as a mask, the second hard mask 5 made of C is etched to transfer the pattern, and the first hard mask 4 is formed in the recess. The surface of was exposed. This step uses an inductively coupled plasma (ICP) RIE apparatus, using O ₂ as a process gas, a chamber pressure of 0.1 Pa, a coil RF power and a platen RF power of 100 W and 50 W, respectively, and an etching time of 20 seconds. Went as.

  As shown in FIG. 10 (f), Cr having a thickness of 30 nm was formed as the implantation depth adjusting layer 9 on the medium on which the uneven pattern was formed up to the second hard mask 5.

As shown in FIG. 10G, the magnetism of the region corresponding to the pattern concave portion of the magnetic recording layer 2 is changed through the implantation depth adjusting layer 9 made of Cr, the first hard mask 4 made of Mo, and the DLC layer 3. Deactivated. As a result, a nonmagnetic region 8 was formed in the magnetic recording layer 2. This deactivation of magnetism uses a mixed gas of He and N ₂ having a partial pressure ratio of 1: 1 by an ECR (electron cyclotron resonance) ion gun, a gas pressure of 0.04 Pa, a microwave power of 1000 W, a pressurization voltage of 5000 V, The treatment time was 100 seconds.

As shown in FIG. 10 (h), the remaining implantation depth adjusting layer 9 was removed. This step was performed by an RIE apparatus using Cl ₂ as a process gas, a chamber pressure of 1 Pa, a power of 400 W, and an etching time of 20 seconds.

As shown in FIG. 10 (i), the remaining first hard mask (Mo) 4 was removed together with the upper layer. This step was performed by immersing the medium in aqueous hydrogen peroxide and holding it for 1 minute. As a result, the first hard mask 4 was peeled off from the DLC layer 3. Furthermore, the surface was cleaned with H ₂ plasma.

  As shown in FIG. 10J, a protective layer 11 was formed by CVD (chemical vapor deposition), and a lubricant was applied to obtain a patterned medium.

  The produced medium was mounted on a drive and a fringe test was performed. The magnetic Land width of the medium was 54 nm, the Groove width was 16 nm, the effective recording head width (MWW) was 80 nm, the effective reproducing head width (MRW) was 50 nm, and error rate measurement was performed after 1000 adjacent recordings. The error rate was 10 −5 or less, and it was confirmed that the DTR medium operated without any problem.

[Example 3]
A magnetic recording medium was manufactured by the method shown in FIG. Furthermore, the performance was evaluated.

  As shown in FIGS. 11A to 11E, each layer was formed and a pattern was formed. These steps were performed in the same manner as the steps shown in FIGS. 10A to 10E of Example 2.

  As shown in FIG. 11F, using the patterned second hard mask 5 as a mask, the first hard mask 4 made of Mo is etched to transfer the pattern, and the surface of the DLC layer 3 is formed by the recess. Exposed. This treatment was performed by an ion milling apparatus using Ar as a process gas, a chamber pressure of 0.05 Pa, an acceleration voltage of 400 V, and a treatment time of 10 seconds.

As shown in FIG. 11G, using the patterned first hard mask 4 as a mask, the DLC layer 3 was etched to transfer the pattern, and the surface of the magnetic recording layer 2 was exposed at the recesses. This process uses an inductively coupled plasma (ICP) RIE apparatus using O ₂ as a process gas, a chamber pressure of 0.1 Pa, a coil RF power and a platen RF power of 100 W and 50 W, respectively, and an etching time of 20 seconds. Went as.

  As shown in FIG. 11 (h), W having a thickness of 30 nm was formed as the implantation depth adjusting layer 9 on the medium on which the uneven pattern was formed up to the DLC layer 3.

As shown in FIG. 11 (i), the magnetism of the region corresponding to the pattern concave portion of the magnetic recording layer 2 was deactivated through the implantation depth adjusting layer 9 made of W. This process was performed by an ECR (electron cyclotron resonance) ion gun using N ₂ gas at a gas pressure of 0.04 Pa, a microwave power of 1000 W, a pressurization voltage of 5000 V, and a treatment time of 50 seconds. By this treatment, the film thickness of the implantation depth adjusting layer 9 was reduced from 30 nm to 2 nm.

  As shown in FIG. 11 (j), the remaining first hard mask (Mo) 4 was removed together with the upper layer. This step was performed by immersing the medium in aqueous hydrogen peroxide and holding it for 1 minute. As a result, the first hard mask 4 is peeled off from the DLC layer 3, the implantation depth adjusting layer 9 is formed on the nonmagnetic region 8 of the magnetic recording layer 2, and the DLC layer 3 is formed on the region where the magnetism is maintained. The remaining. The film thickness of the remaining DLC layer 3 was 3 nm, the film thickness of the implantation depth adjusting layer 9 was 2 nm, and the resulting unevenness difference was 1 nm.

  As shown in FIG. 11 (k), a protective layer 11 was formed by CVD (chemical vapor deposition), and a lubricant was applied to obtain a patterned medium.

  The produced medium was mounted on a drive and a fringe test was performed. The magnetic Land width of the medium was 54 nm, the Groove width was 16 nm, the effective recording head width (MWW) was 80 nm, the effective reproducing head width (MRW) was 50 nm, and error rate measurement was performed after 1000 adjacent recordings. The error rate was 10 −5 or less, and it was confirmed that the DTR medium operated without any problem.

[Example 4]
A magnetic recording medium was manufactured by the method shown in FIG. Furthermore, the performance was evaluated.

  As shown in FIGS. 12A to 12E, each layer was formed and a pattern was formed. These steps were performed in the same manner as the steps shown in FIGS. 10A to 10E of Example 2.

  As shown in FIG. 12 (f), using the patterned second hard mask 5 as a mask, the first hard mask 4 made of Mo is etched to transfer the pattern, and the surface of the DLC layer 3 is formed by the recess. Exposed. This step was performed by an ion milling apparatus using Ar as a process gas, a chamber pressure of 0.05 Pa, an acceleration voltage of 400 V, and a processing time of 10 seconds.

As shown in FIG. 12G, using the patterned first hard mask 4 as a mask, the DLC layer 3 was etched to transfer the pattern, and the surface of the magnetic recording layer 2 was exposed at the recesses. This process uses an inductively coupled plasma (ICP) RIE apparatus using O ₂ as a process gas, a chamber pressure of 0.1 Pa, a coil RF power and a platen RF power of 100 W and 50 W, respectively, and an etching time of 20 seconds. Went as.

  As shown in FIG. 12 (h), W having a thickness of 25 nm was formed as the implantation depth adjusting layer 9 on the medium on which the uneven pattern was formed up to the DLC layer 3.

As shown in FIG. 12 (i), the magnetism of the region corresponding to the pattern concave portion of the magnetic recording layer 2 was deactivated through the implantation depth adjusting layer 9 made of W. This process was performed by an ECR (electron cyclotron resonance) ion gun using N ₂ gas at a gas pressure of 0.04 Pa, a microwave power of 1000 W, a pressurization voltage of 5000 V, and a treatment time of 50 seconds. By this treatment, all of the implantation depth adjusting layer 9 was etched, and the concave surface of the magnetic recording layer 2 was also etched by 3 nm.

  As shown in FIG. 12 (j), the remaining first hard mask (Mo) 4 was removed together with the upper layer. This step was performed by immersing the medium in aqueous hydrogen peroxide and holding it for 1 minute. As a result, the first hard mask 4 was peeled off from the DLC layer 3, and the DLC layer 3 remained on the region of the magnetic recording layer 2 where the magnetism was maintained. The film thickness of the remaining DLC layer 3 was 3 nm. Since the surface of the nonmagnetic region 8 was etched by 3 nm, the resulting unevenness difference was 6 nm.

  As shown in FIG. 12 (k), a protective layer 11 was formed by CVD (chemical vapor deposition), and a lubricant was applied to obtain a patterned medium.

  The produced medium was mounted on a drive and a fringe test was performed. The magnetic Land width of the medium was 54 nm, the Groove width was 16 nm, the effective recording head width (MWW) was 80 nm, the effective reproducing head width (MRW) was 50 nm, and error rate measurement was performed after 1000 adjacent recordings. The error rate was 10 −5 or less, and it was confirmed that the DTR medium operated without any problem.

[Example 5]
A DTR medium was produced in the same manner as in Example 1. However, in the process of FIG. 3A, the film thickness of the first hard mask 4 made of Mo that also serves as the implantation depth adjusting layer is set to 5 nm, 10 nm, 20 nm, 30 nm, or 40 nm, and in the process of FIG. Etching was stopped so that the first hard mask 4 remained 1 to 5 nm.

  Further, as Comparative Example 1, the process up to the step of FIG. 3 (e) was performed in the same manner as in Example 1, and then the first hard mask 4 and DLC layer 3 made of Mo that also served as the implantation depth adjusting layer were etched. Magnetic deactivation similar to that of Example 2 was performed to prepare a medium.

The produced medium was mounted on a drive and a fringe test was performed. The magnetic Land width of the medium was 54 nm, the Groove width was 16 nm, the effective recording head width (MWW) was 80 nm, the effective reproducing head width (MRW) was 50 nm, and the error rate was measured after 1000 adjacent recordings. Furthermore, Ms of the nonmagnetic region of the medium was measured by VSM. The results are shown in Table 1.

  From the result of the error rate ER, it was confirmed that the medium provided with the injection depth adjusting layer at the time of deactivation of the magnet exhibits excellent performance as a DTR medium. Further, from the result of Ms, it was found that the medium in which the injection depth adjusting layer was provided at the time of deactivation of the magnetism was sufficiently deactivated as compared with Comparative Example 1.

Also in Examples 2, 3 and 4, media were manufactured by changing the thickness of the injection depth adjusting layer and compared with the comparative example. As a result, similarly to the medium of Example 1, it was found that providing the injection depth adjusting layer can sufficiently deactivate magnetism, and the error rate can be kept low.

[Example 6]
A DTR medium was produced in the same manner as in Example 1. However, in the magnetic deactivation step of FIG. 3 (f), ion beam irradiation was stopped so that the film thickness of the remaining implantation depth adjusting layer was 20 nm, 10 nm, 5 nm, or 2 nm.

  Further, as Comparative Example 2, a DTR medium was manufactured by performing ion implantation at the energy of 30 keV using the same gas as in Example 2 in the magnetic deactivation process of FIG. When such high energy ion implantation is performed, the thickness of the implantation depth adjusting layer does not decrease.

The produced medium was mounted on a drive and a fringe test was performed. The magnetic Land width of the medium was 54 nm, the Groove width was 16 nm, the effective recording head width (MWW) was 80 nm, the effective reproducing head width (MRW) was 50 nm, and the error rate was measured after 1000 adjacent recordings. Furthermore, Ms of the nonmagnetic region of the medium was measured by VSM. The results are shown in Table 2.

  In the medium according to the embodiment, the magnetism was sufficiently deactivated, and a good error rate was obtained. On the other hand, in Comparative Example 2, although the magnetism was sufficiently deactivated, the error rate could not be measured. When the media was removed from the drive and investigated, it was found that damage was spreading to the side due to high-energy ion implantation. From the above results, it was shown that by irradiating the ion beam with low energy while reducing the film thickness of the implantation depth adjustment layer, the medium can be patterned without damage to the side.

  Also in Examples 2, 3 and 4, media were produced by changing the amount of decrease in the injection depth adjusting layer, and compared with the comparative example. As a result, similarly to the medium of Example 1, by deactivating while reducing the film thickness of the implantation depth adjusting layer, damage to the side does not occur, magnetism is sufficiently deactivated, and the Leller rate is kept low. I found out that I could do it.

[Example 7]
A DTR medium was produced in the same manner as in Example 1. However, in the step of FIG. 3A, as an ion beam to be irradiated, a mixed gas of He, Ne, Ar, Kr, Xe, N ₂ , O ₂ , H ₂ , He—N _{2, or} a mixed gas of Ne—H ₂ is used. Alternatively, a mixed gas of Ar—O ₂ was used. Furthermore, the irradiation energy was changed to such a condition that there was no damage on the side. Comparative example 1 was produced as a comparative example.

The produced medium was mounted on a drive and a fringe test was performed. The magnetic Land width of the medium was 54 nm, the Groove width was 16 nm, the effective recording head width (MWW) was 80 nm, the effective reproducing head width (MRW) was 50 nm, and the error rate was measured after 1000 adjacent recordings. Furthermore, Ms of the nonmagnetic region of the medium was measured by VSM. The results are shown in Table 3.

  In the medium according to the embodiment, the magnetism was sufficiently deactivated, and a good error rate was obtained. On the other hand, in Comparative Example 1, Ms in the non-recording area could not be lowered to 0, and the error rate could not be measured. Even when various gases are used in the ion beam, it has been found that the medium according to the embodiment exhibits excellent performance.

  Also in Examples 2, 3 and 4, media were produced by changing the type of gas used, and compared with the comparative example. As a result, similar to the medium of Example 1, it was found that excellent performance was exhibited even when various gases were used.

[Example 8]
A DTR medium was produced in the same manner as in Example 2. However, as the material for the implantation depth adjusting layer formed in the step of FIG. 10 (f), C, C _0.9 N _0.1 , Si, SiO ₂ , Si ₃ N ₄ , Si ₅ C ₁₉ , Ag, Au Cu, Pd, Pt, Ru, CoPt, CoCrPt, CoCrPt—SiO ₂ , Al, Cr, Hf, Mo, Nb, Ta, Ti, V, W, or Zr were used. In addition, peeling of the injection depth adjusting layer was appropriately selected as shown in Table 4 according to the material used as the injection depth adjusting layer. Further, Comparative Example 1 was produced as a comparative example.

The produced medium was mounted on a drive and a fringe test was performed. The magnetic Land width of the medium was 54 nm, the Groove width was 16 nm, the effective recording head width (MWW) was 80 nm, the effective reproducing head width (MRW) was 50 nm, and the error rate was measured after 1000 adjacent recordings. Furthermore, Ms of the nonmagnetic region of the medium was measured by VSM. The results are shown in Table 4.

  In the medium according to the embodiment, the magnetism was sufficiently deactivated, and a good error rate was obtained. On the other hand, in Comparative Example 1, Ms in the non-recording area could not be lowered to 0, and the error rate could not be measured. Even when various materials are used as the injection depth adjusting layer, it has been found that the medium according to the embodiment exhibits excellent performance.

  Also in Examples 1, 3 and 4, media were produced by changing the material used as the injection depth adjusting layer, and compared with the comparative example. As a result, similar to the medium of Example 2, it was found that excellent performance was exhibited even when various materials were used as the injection depth adjusting layer.

[Example 9]
A magnetic recording medium was manufactured by the same method as in Example 1. Furthermore, the performance was evaluated. However, 10 nm of Ta was laminated as the second implantation depth adjustment layer between the first hard mask (Mo) 4 and the second hard mask (C) 5 as the implantation depth adjustment layer and the release layer. Furthermore, the thickness of Mo was reduced to 5 nm.

As shown in FIG. 3A, on a glass substrate 1, a 40 nm thick soft magnetic layer (CoZrNb) (not shown), a 20 nm thick orientation control underlayer (Ru) (not shown), and 20 nm thick magnetic recording layer 2 (CoCrPt—SiO ₂ ), 2 nm thick DLC protective film 3, 5 nm thick first hard mask (Mo) 4, 5 nm thick second implantation depth adjusting layer ( Ta) (not shown), a second hard mask (C) 5 having a thickness of 30 nm, and a third hard mask (Si) 6 having a thickness of 3 nm were formed. A resist 7 was spin-coated on the third hard mask 6 so as to have a thickness of 80 nm. The stamper was arranged so that the uneven surface thereof faces the resist 7.

  As shown in FIG. 3B, a stamper was imprinted on the resist 7, and the uneven pattern of the stamper was transferred to the resist 7. Thereafter, the stamper was removed. Resist residue remained on the bottom of the concave portion of the concave-convex pattern transferred to the resist 7.

As shown in FIG. 3C, the resist residue in the recesses was removed by dry etching, and the surface of the third hard mask 6 was exposed. In this process, CF ₄ is used as a process gas by an inductively coupled plasma (ICP) RIE apparatus, the chamber pressure is 0.1 Pa, the coil RF power and the platen RF power are 100 W and 50 W, respectively, and the etching time is 60 seconds. Went as.

As shown in FIG. 3D, the patterned resist 7 is used as a mask, the pattern is transferred to the third hard mask 6 using ion beam etching, and the second hard mask 5 is exposed in the recesses. . In this process, CF ₄ is used as a process gas by an inductively coupled plasma (ICP) RIE apparatus, the chamber pressure is 0.1 Pa, the coil RF power and the platen RF power are 100 W and 50 W, respectively, and the etching time is 20 seconds. Went as.

As shown in FIG. 3E, using the patterned third hard mask 6 as a mask, the second hard mask 5 made of C is etched to transfer the pattern, and the first hard mask 4 is formed in the recess. The surface of was exposed. Using an inductively coupled plasma (ICP) RIE apparatus, O ₂ was used as a process gas, the chamber pressure was 0.1 Pa, the coil RF power and the platen RF power were 100 W and 50 W, respectively, and the etching time was 30 seconds.

As shown in FIG. 3F, the region corresponding to the pattern concave portion of the magnetic recording layer 2 through the second deactivation depth adjusting layer made of Ta, the first hard mask 4 made of Mo, and the DLC layer 3 The magnetism was deactivated. As a result, a nonmagnetic region 8 was formed in the magnetic recording layer 2. The deactivation of magnetism was performed with an ECR (electron cyclotron resonance) ion gun using N ₂ gas at a gas pressure of 0.04 Pa, a microwave power of 1000 W, a pressurization voltage of 5000 V, and a treatment time of 60 seconds. At this time, all Ta was etched away.

  As shown in FIG. 3G, the remaining first hard mask (Mo) 4 was removed together with the upper layer. This step was performed by immersing the medium in aqueous hydrogen peroxide and holding it for 1 minute. As a result, the first hard mask 4 was peeled off from the DLC layer 3.

  As shown in FIG. 3H, a protective layer 11 was formed by CVD (chemical vapor deposition), and a lubricant was applied to obtain a patterned medium.

  The produced medium was mounted on a drive and a fringe test was performed. The magnetic Land width of the medium was 54 nm, the Groove width was 16 nm, the effective recording head width (MWW) was 80 nm, the effective reproducing head width (MRW) was 50 nm, and error rate measurement was performed after 1000 adjacent recordings. The error rate was 10 −5 or less, and it was confirmed that the DTR medium operated without any problem. As described above, it has been shown that even when the deactivation depth adjusting layer is made of two layers of Mo and Ta, the medium can be produced without any problem and can be driven.

  DESCRIPTION OF SYMBOLS 1 ... Substrate, 2 ... Magnetic recording layer, 3 ... Diamond like carbon (DLC) layer, 4 ... 1st hard mask, 5 ... 2nd hard mask, 6 ... 3rd hard mask, 7 ... Resist, 8 ... Nonmagnetic region, 9 ... implantation depth adjusting layer, 10 ... mask, 11 ... protective layer, 100 ... magnetic recording medium, 130 ... head slider, 140 ... spindle motor, 150 ... magnetic recording device, 154 ... suspension, 156 ... voice coil Motor 157... Pivot 160 Actuator arm 210 Servo area 211 Preamble part 212 Address part 213 Burst part 220 Data area 221 Discrete track 222 Magnetic dot

According to the embodiment, an implantation depth adjusting layer including a material to be etched by ion beam irradiation of the chemical species is formed on the magnetic recording layer including a material to be inactivated by the implantation of the chemical species, and the implantation is performed. Irradiating the ion beam to the depth adjustment layer, and implanting the chemical species into a part of the magnetic recording layer through the implantation depth adjustment layer, etching the implantation depth adjustment layer by the ion beam, Reducing the thickness of the implantation depth adjustment layer is provided.

According to the embodiment, a material that is etched by ion beam irradiation of the chemical species on the magnetic recording layer including a material that is inactivated by implantation of the chemical species , and C _x N _y (y ≦ x), Si, SiO ₂ , Si _x N _y (y ≦ 4x / 3), Si _x C _y (y ≦ 25x), Ag, Au, Cu, Pd, Pt, Ru, CoPt, CoCrPt, CoCrPt—SiO ₂ , Al, Forming an implantation depth adjusting layer including at least one material selected from the group consisting of Cr, Hf, Mo, Nb, Ta, Ti, V, W, and Zr; and applying the ion beam to the implantation depth adjusting layer. Irradiation and etching the implantation depth adjusting layer by the ion beam while implanting the chemical species into a part of the magnetic recording layer through the implantation depth adjusting layer, thereby adjusting the implantation depth. There is provided a method of manufacturing a patterned medium comprising reducing the thickness of the layer.

The produced medium was mounted on a drive and a fringe test was performed. The magnetic Land width of the medium was 54 nm, the Groove width was 16 nm, the effective recording head width (MWW) was 80 nm, the effective reproducing head width (MRW) was 50 nm, and error rate measurement was performed after 1000 adjacent recordings. The error rate was 10 −5 or less, and it was confirmed that the DTR medium operated without any problem. As described above, it has been shown that even when the deactivation depth adjusting layer is made of two layers of Mo and Ta, the medium can be produced without any problem and can be driven.
The invention described in the original claims is appended below.
[1]
Forming a mask having a concavo-convex pattern on the magnetic recording layer, and deactivating magnetism in the region of the magnetic recording layer corresponding to the concave portion of the mask,
Including deactivating magnetism of the magnetic recording layer by irradiation of an ion beam through an implantation depth adjusting layer provided on the magnetic recording layer;
A method for producing a patterned medium in which the film thickness of the implantation depth adjusting layer decreases with the progress of deactivation of magnetism, and the ion beam penetration depth increases.
[2]
The manufacturing method according to [1], wherein an ion beam penetration depth upon completion of deactivation is located below the magnetic recording layer.
[3]
The manufacturing method according to [1], wherein an ion beam penetration depth at the start of deactivation is located in the magnetic recording layer.
[4]
The manufacturing method according to [1], wherein an ion beam penetration depth at the start of deactivation is located above the magnetic recording layer.
[5]
The production method according to [1], wherein the injection depth adjusting layer disappears due to deactivation.
[6]
The manufacturing method according to [1], wherein the injection depth adjusting layer remains after deactivation, and the remaining injection depth adjusting layer is peeled off.
[7]
The manufacturing method according to [1], wherein the implantation depth adjusting layer is formed when the mask is formed.
[8]
The manufacturing method according to [1], wherein the implantation depth adjusting layer is formed after the concave / convex pattern of the mask is formed.
[9]
The manufacturing method according to [1], wherein a diamond-like carbon layer is provided between the implantation depth adjusting layer and the magnetic recording layer.
[10]
On the magnetic recording layer, a diamond-like carbon layer, the implantation depth adjusting layer that also serves as a release layer, a mask layer, and a resist are sequentially formed.
Forming a concavo-convex pattern on the mask layer;
Deactivating magnetism of the magnetic recording layer using the mask layer as a mask,
Peel off the injection depth adjusting layer
The production method according to [7] or [9].
[11]
On the magnetic recording layer, a diamond-like carbon layer, a release layer, the implantation depth adjusting layer, a mask layer, and a resist are sequentially formed,
Forming a concavo-convex pattern on the mask layer;
Deactivating magnetism of the magnetic recording layer using the mask layer as a mask,
Peel off the release layer
The production method according to [7] or [9].
[12]
On the magnetic recording layer, a diamond-like carbon layer, a release layer, a mask layer, and a resist are sequentially formed,
Forming a concavo-convex pattern on the mask layer;
Forming the injection depth adjusting layer;
Deactivating magnetism of the magnetic recording layer using the mask layer as a mask,
Peel off the release layer
The production method according to [8] or [9].
[13]
The production method according to [1], wherein the acceleration voltage during ion beam irradiation is constant during the process.
[14]
The production method according to [1], wherein the ion beam source is a gas selected from the group consisting of He, Ne, Ar, Kr, Xe, N ₂ , O ₂ and H ₂ or a mixture thereof.
[15]
The composition of the implantation depth adjusting layer is C, C _x N _y (y ≦ x), Si, SiO ₂ , Si _x N _y (y ≦ 4x / 3), Si _x C _y (y ≦ 25x), Ag, At least one material selected from the group consisting of Au, Cu, Pd, Pt, Ru, CoPt, CoCrPt, CoCrPt—SiO ₂ , Al, Cr, Hf, Mo, Nb, Ta, Ti, V, W and Zr The production method according to [1], which comprises a main component.
[16]
A magnetic recording apparatus on which the magnetic recording medium manufactured by the manufacturing method according to [1] is mounted.

Claims (16)

Forming a mask having a concavo-convex pattern on the magnetic recording layer, and deactivating magnetism in the region of the magnetic recording layer corresponding to the concave portion of the mask,
Including deactivating magnetism of the magnetic recording layer by irradiation of an ion beam through an implantation depth adjusting layer provided on the magnetic recording layer;
A method for producing a patterned medium in which the film thickness of the implantation depth adjusting layer decreases with the progress of deactivation of magnetism, and the ion beam penetration depth increases.   2. The manufacturing method according to claim 1, wherein an ion beam penetration depth upon completion of deactivation is located below the magnetic recording layer.   The manufacturing method according to claim 1, wherein an ion beam penetration depth at the start of deactivation is located in the magnetic recording layer.   The manufacturing method according to claim 1, wherein an ion beam penetration depth at the start of deactivation is located above the magnetic recording layer.   The manufacturing method according to claim 1, wherein the injection depth adjusting layer disappears due to deactivation.   The manufacturing method according to claim 1, wherein the injection depth adjusting layer remains after deactivation, and the remaining injection depth adjusting layer is peeled off.   The manufacturing method according to claim 1, wherein the implantation depth adjusting layer is formed when the mask is formed.   The manufacturing method according to claim 1, wherein the implantation depth adjusting layer is formed after the concave / convex pattern of the mask is formed.   The manufacturing method according to claim 1, wherein a diamond-like carbon layer is provided between the implantation depth adjusting layer and the magnetic recording layer. On the magnetic recording layer, a diamond-like carbon layer, the implantation depth adjusting layer that also serves as a release layer, a mask layer, and a resist are sequentially formed.
Forming a concavo-convex pattern on the mask layer;
Deactivating magnetism of the magnetic recording layer using the mask layer as a mask,
The manufacturing method according to claim 7 or 9, comprising peeling the injection depth adjusting layer. On the magnetic recording layer, a diamond-like carbon layer, a release layer, the implantation depth adjusting layer, a mask layer, and a resist are sequentially formed,
Forming a concavo-convex pattern on the mask layer;
Deactivating magnetism of the magnetic recording layer using the mask layer as a mask,
The manufacturing method of Claim 7 or 9 including peeling the said peeling layer. On the magnetic recording layer, a diamond-like carbon layer, a release layer, a mask layer, and a resist are sequentially formed,
Forming a concavo-convex pattern on the mask layer;
Forming the injection depth adjusting layer;
Deactivating magnetism of the magnetic recording layer using the mask layer as a mask,
The manufacturing method of Claim 8 or 9 including peeling the said peeling layer.   The manufacturing method according to claim 1, wherein an acceleration voltage at the time of ion beam irradiation is constant during the process. The manufacturing method according to claim 1, wherein the ion beam source is a gas selected from the group consisting of He, Ne, Ar, Kr, Xe, N ₂ , O ₂ and H ₂ or a mixture thereof. The composition of the implantation depth adjusting layer is C, C _x N _y (y ≦ x), Si, SiO ₂ , Si _x N _y (y ≦ 4x / 3), Si _x C _y (y ≦ 25x), Ag, At least one material selected from the group consisting of Au, Cu, Pd, Pt, Ru, CoPt, CoCrPt, CoCrPt—SiO ₂ , Al, Cr, Hf, Mo, Nb, Ta, Ti, V, W and Zr The manufacturing method of Claim 1 which makes it a main component.   A magnetic recording apparatus on which a magnetic recording medium manufactured by the manufacturing method according to claim 1 is mounted.

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